Please answer the following questions which I have not done.

Dear student,

a. A reply may be sent by you.
b. Would a lift be taken by you?
c. Your elders ought to be respected by you.
d. A prize has been given to me by the Principal.
e. A bicycle was bought for me by my father.
f. By whom is the door being knocked (at)?
g. The case was enquired into by the police.
h. Peace is longed for by everybody.
i. We were surprised by his history.
j. Will I not be helped by you?
k. Which letter was written by you yesterday?

Regards